This invention relates to metallized chloroplasts wherein catalytic metals are precipitated on chloroplast membranes. This composition is then deposited on a non-reacting solid support medium for use in the conversion of light energy to chemical energy by way of a photosynthetic reaction.
In general, photosynthetic reactions that occur in nature involve the conversion of solar energy into chemical energy by formation of complex carbohydrates from carbon dioxide and water in the presence of chloroplasts. Studies have been done on the possibility of using solar energy and chloroplasts to perform other reactions such as splitting of water to form gaseous hydrogen and oxygen. This has typically been done utilizing chloroplasts, a biocatalyst that permits an electron transfer reaction to evolve a product, and an electron relay that transports electrons from the chloroplast to the biocatalyst. Since these reactions have been done in aqueous suspension an electron relay was required. The biocatalysts have typically been naturally occurring biocatalysts such as hydrogenase, although inorganic catalysts have been proposed in order to develop a partially synthetic system. Inorganic catalysts, such as precious metals, subjected to procedures similar to those described for the natural biocatalysts have given unfavorable results because of the oxidation of the electron relay upon the evolution of oxygen. Therefore, it is necessary to develop a process to eliminate the oxidation of the electron relay so that the evolution of oxygen is not a problem.